PCI: Add generic domain handling
The handling of PCI domains (or PCI segments in ACPI speak) is usually a
straightforward affair but its implementation is currently left to the
architectural code, with pci_domain_nr(b) querying the value of the domain
associated with bus b.
This patch introduces CONFIG_PCI_DOMAINS_GENERIC as an option that can be
selected if an architecture wants a simple implementation where the value
of the domain associated with a bus is stored in struct pci_bus.
The architectures that select CONFIG_PCI_DOMAINS_GENERIC will then have to
implement pci_bus_assign_domain_nr() as a way of setting the domain number
associated with a root bus. All child buses except the root bus will
inherit the domain_nr value from their parent.
Signed-off-by: Catalin Marinas <Catalin.Marinas@arm.com>
[Renamed pci_set_domain_nr() to pci_bus_assign_domain_nr()]
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Arnd Bergmann <arnd@arndb.de>
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index e3cf8a2..636d1c9 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -485,7 +485,7 @@
}
}
-static struct pci_bus *pci_alloc_bus(void)
+static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
{
struct pci_bus *b;
@@ -500,6 +500,10 @@
INIT_LIST_HEAD(&b->resources);
b->max_bus_speed = PCI_SPEED_UNKNOWN;
b->cur_bus_speed = PCI_SPEED_UNKNOWN;
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+ if (parent)
+ b->domain_nr = parent->domain_nr;
+#endif
return b;
}
@@ -671,7 +675,7 @@
/*
* Allocate a new bus, and inherit stuff from the parent..
*/
- child = pci_alloc_bus();
+ child = pci_alloc_bus(parent);
if (!child)
return NULL;
@@ -1761,13 +1765,14 @@
char bus_addr[64];
char *fmt;
- b = pci_alloc_bus();
+ b = pci_alloc_bus(NULL);
if (!b)
return NULL;
b->sysdata = sysdata;
b->ops = ops;
b->number = b->busn_res.start = bus;
+ pci_bus_assign_domain_nr(b, parent);
b2 = pci_find_bus(pci_domain_nr(b), bus);
if (b2) {
/* If we already got to this bus through a different bridge, ignore it */
